[IDC-1939] Debug Dialog part 1 (#2011)

* WIP debug dialog

* Rename the p10 downloader extension to debugger extension, add button to toolbar. Deactivate it by default.

* Fix unit tests

extensions/debugging/.webpack/webpack.dev.js

@@ -0,0 +1,8 @@
+const path = require('path');
+const webpackCommon = require('./../../../.webpack/webpack.commonjs.js');
+const SRC_DIR = path.join(__dirname, '../src');
+const DIST_DIR = path.join(__dirname, '../dist');
+
+module.exports = (env, argv) => {
+  return webpackCommon(env, argv, { SRC_DIR, DIST_DIR });
+};